feat(fetch): pass validation error to hooks

[kwonoj]

Attempt to close #42.

PR adjusts hooks with validation errors, pass it to the hooks before throw it. To allow distinguish between error types, now error context have type property. The existing behavior is preserved if hooks are not provided.

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Name	Status	Preview	Comments	Updated (UTC)
better-fetch-docs	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Jul 20, 2025 6:57am

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